tcm_fc: Remove use of transport_do_task_sg_chain()

With the modern target core, se_cmd->t_data_sg already points to a
sglist that covers the whole command.  So task_sg chaining is needless
overhead and obfuscation -- instead of splicing the split up task
sglists back into one list, we can just use the original list directly.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Kiran Patil <Kiran.patil@intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

3 files changed, 5 insertions, 18 deletions

diff --git a/drivers/target/tcm_fc/tfc_cmd.c b/drivers/target/tcm_fc/tfc_cmd.c
index a375f257aabc..f03fb9730f5b 100644
--- a/drivers/target/tcm_fc/tfc_cmd.c
+++ b/drivers/target/tcm_fc/tfc_cmd.c
@@ -215,20 +215,10 @@ int ft_write_pending(struct se_cmd *se_cmd)
                  */
                 if ((ep->xid <= lport->lro_xid) &&
                     (fh->fh_r_ctl == FC_RCTL_DD_DATA_DESC)) {
-                        if (se_cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
-                                /*
-                                 * cmd may have been broken up into multiple
-                                 * tasks. Link their sgs together so we can
-                                 * operate on them all at once.
-                                 */
-                                transport_do_task_sg_chain(se_cmd);
-                                cmd->sg = se_cmd->t_tasks_sg_chained;
-                                cmd->sg_cnt =
-                                        se_cmd->t_tasks_sg_chained_no;
-                        }
-                        if (cmd->sg && lport->tt.ddp_target(lport, ep->xid,
-                                                            cmd->sg,
-                                                            cmd->sg_cnt))
+                        if ((se_cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) &&
+                            lport->tt.ddp_target(lport, ep->xid,
+                                                 se_cmd->t_data_sg,
+                                                 se_cmd->t_data_nents))
                                 cmd->was_ddp_setup = 1;
                 }
         }
diff --git a/drivers/target/tcm_fc/tfc_conf.c b/drivers/target/tcm_fc/tfc_conf.c
index 2948dc944619..9501844fae2d 100644
--- a/drivers/target/tcm_fc/tfc_conf.c
+++ b/drivers/target/tcm_fc/tfc_conf.c
@@ -576,9 +576,6 @@ int ft_register_configfs(void)
         }
         fabric->tf_ops = ft_fabric_ops;
 
-        /* Allowing support for task_sg_chaining */
-        fabric->tf_ops.task_sg_chaining = 1;
-
         /*
          * Setup default attribute lists for various fabric->tf_cit_tmpl
          */
diff --git a/drivers/target/tcm_fc/tfc_io.c b/drivers/target/tcm_fc/tfc_io.c
index dc7c0db26e20..071a505f98fc 100644
--- a/drivers/target/tcm_fc/tfc_io.c
+++ b/drivers/target/tcm_fc/tfc_io.c
@@ -228,7 +228,7 @@ void ft_recv_write_data(struct ft_cmd *cmd, struct fc_frame *fp)
                                 "payload, Frame will be dropped if"
                                 "'Sequence Initiative' bit in f_ctl is"
                                 "not set\n", __func__, ep->xid, f_ctl,
-                                cmd->sg, cmd->sg_cnt);
+                                se_cmd->t_data_sg, se_cmd->t_data_nents);
                 /*
                  * Invalidate HW DDP context if it was setup for respective
                  * command. Invalidation of HW DDP context is requited in both